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101.
José Luis Lobato Miguelez Julio Moreno DomingoTania Arriba Olivenza Saioa Ajuriagogeascoa AndradaMiguel López Valverde 《Revista espa?ola de geriatría y gerontología》2012
Background
The number of elderly patients with breast cancer is increasing, and a large proportion of these older patients do not receive conventional treatment. Clinical and biological characteristics of tumours at this age and survival according to local or systemic therapy were analysed.Material and method
A total of 96 consecutive early breast cancer patients over 80 years of age diagnosed in our Unit between January 2002 and September 2008 were retrospectively investigated. Of them, 54 underwent surgery with or without adjuvant hormonal treatment, and 42 received primary hormonal therapy.Results
Tumours of patients 80 years old or older had more favourable biological characteristics, including expression of steroid receptors, and absence of c-erb B2 expression. Overall survival was 50 months for the group subjected to surgery, and 44 months for the group who did not undergo surgery. The survival free of local recurrence in the surgery group was 44 months, whereas it was 18 months in the non-surgery group.Conclusion
In a cohort of patients aged 80 years and older, survival was similar in those who received hormonal or surgical therapy, although the former had a shorter period of progression-free survival or local recurrence. 相似文献102.
The ectomycorrhizal fungus Tuber melanosporum fruits in association with Quercus in natural forests of Spain. Some of these stands are managed to keep an open canopy and meet the habitat requirements of the fungus. However, there are few quantitative studies analysing in these forests the relationship between soil environment and T. melanosporum. Eight forest stands which produce T. melanosporum have been monitored for 6 years in order to characterise the below-ground ectomycorrhizal community and to assess its temporal dynamics after experimental canopy opening. The br?lé, the ground where T. melanosporum fruits, shows a distinct ectomycorrhizal community, characterised by lower density of active ectomycorrhizal tips, lower morphotype richness per soil volume, higher abundance of T. melanosporum and lower abundance of Cenococcum geophilum than soil closest to the trunk of the host Quercus ilex. Opening the canopy has not stimulated an increase in T. melanosporum, suggesting that a shift in the soil environment alone will not trigger the formation of new truffières in the short term. The dry climate of these truffières may be a factor as T. melanosporum abundance appears to be sensitive to annual weather conditions. 相似文献
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Toffanello ED Perissinotto E Sergi G Zambon S Musacchio E Maggi S Coin A Sartori L Corti MC Baggio G Crepaldi G Manzato E 《PloS one》2012,7(4):e34950
Background
The role of Vitamin D in musculoskeletal functionality among elderly people is still controversial. We investigated the association between serum 25-hydroxyvitamin D (25OHD) levels and physical performance in older adults.Methods
2694 community-dwelling elderly women and men from the Progetto Veneto Anziani (Pro.V.A.) were included. Physical performances were assessed by: tandem test, 5 timed chair stands (TCS), gait speed, 6-minute walking (6 mW) distance, handgrip strength, and quadriceps strength. For each test, separate general linear models and loess plots were obtained in both genders, in relation to serum 25OHD concentrations, controlling for several potential confounders.Results
Linear associations with 25OHD levels were observed for TCS, gait speed, 6 mW test and handgrip strength, but not for tandem test and quadriceps strength. After adjusting for potential confounders, linear associations with 25OHD levels were still evident for the 6 mW distance in both genders (p = .0002 in women; <.0001 in men), for TCS in women (p = .004) and for gait speed (p = .0006) and handgrip strength (p = .03) in men. In loess analyses, performance in TCS in women, in gait speed and handgrip strength in men and in 6 mW in both genders, improved with increasing levels of 25OHD, with most of the improvements occurring for 25OHD levels from 20 to 100 nmol/L.Conclusion
lower 25OHD levels are associated with a worse coordination and weaker strength (TCS) in women, a slower walking time and a lower upper limb strength in men, and a weaker aerobic capacity (6 mW) in both genders. For optimal physical performances, 25OHD concentrations of 100 nmol/L appear to be more advantageous in elderly men and women, and Vitamin D supplementation should be encouraged to maintain their 25OHD levels as high as this threshold. 相似文献106.
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109.
González S Moreno-Delgado D Moreno E Pérez-Capote K Franco R Mallol J Cortés A Casadó V Lluís C Ortiz J Ferré S Canela E McCormick PJ 《PLoS biology》2012,10(6):e1001347
The role of the pineal gland is to translate the rhythmic cycles of night and day encoded by the retina into hormonal signals that are transmitted to the rest of the neuronal system in the form of serotonin and melatonin synthesis and release. Here we describe that the production of both melatonin and serotonin by the pineal gland is regulated by a circadian-related heteromerization of adrenergic and dopamine D4 receptors. Through α1
B-D4 and β1-D4 receptor heteromers dopamine inhibits adrenergic receptor signaling and blocks the synthesis of melatonin induced by adrenergic receptor ligands. This inhibition was not observed at hours of the day when D4 was not expressed. These data provide a new perspective on dopamine function and constitute the first example of a circadian-controlled receptor heteromer. The unanticipated heteromerization between adrenergic and dopamine D4 receptors provides a feedback mechanism for the neuronal hormone system in the form of dopamine to control circadian inputs. 相似文献
110.
I Le Viol F Jiguet L Brotons S Herrando A Lindström JW Pearce-Higgins J Reif C Van Turnhout V Devictor 《Biology letters》2012,8(5):780-782
Biotic homogenization (BH) is a process whereby some species (losers) are systematically replaced by others (winners). While this process has been related to the effects of anthropogenic activities, whether and how BH is occurring across regions and the role of native species as a driver of BH has hardly been investigated. Here, we examine the trend in the community specialization index (CSI) for 234 native species of breeding birds at 10 111 sites in six European countries from 1990 to 2008. Unlike many BH studies, CSI uses abundance information to estimate the balance between generalist and specialist species in local assemblages. We show that bird communities are more and more composed of native generalist species across regions, revealing a strong, ongoing BH process. Our result suggests a rapid and non-random change in community composition at a continental scale is occurring, most likely driven by anthropogenic activities. 相似文献